The study of morphological changes in the kidneys of white rats after intramuscular injection of insulin at a dose of 1 IU/kg of body weight was carried out. The insulin effect was amplified using stress models of immobilization and swimming. Blood samples from tail vein of rats were taken to confirm the action of insulin. At autopsy, the authors conducted the fence venous blood flowing from the kidneys. Comparison with a control group showed that morphological changes in the renal parenchyma were formed after the insulin introduction and characterized by venous congestion in the microvasculature, ischemic changes in the renal parenchyma with areas of hemorrhage, thickening of the basement membrane, expansion of tubules, hydropic degeneration of the epithelium, hypertrophy and enlargement of the loops of the glomeruli. Measurement of glucose in venous blood flowing from the kidneys revealed hyperglycemia. The morphological changes in the tissues of the kidney indicate the development of venous congestion, glomerular hyperfiltration and hypovolemia, hypertension, glycosuria, glycosylation membranes, the deposition of glycogen in the epithelium of kidney tubules, microalbuminuria. The obtained results allow to draw attention to the fact that among the factors of damage during the development of diabetic nephropa-thy, a hyperinsulinemia may have a negative impact